IR-Multitool™
IR Camera Imaging

CDI Carrier Density Imgaging and LIT Lock-In Thermography

Application Area and Benefits

CDI - Carrier density imaging is a fast, spatially resolved lifetime measurement method. It is based on the principle of emission of infrared radiation by free carriers.

A high speed infrared camera (3-5 μm spectral range) with high resolution is applied for measuring the infrared emission from the sample. This overcomes the necessity of scanning the sample in order to receive laterally resolved information. Measurement times can be cut in this setup from hours to minutes or even seconds.

An additional advantage is the absence of any moving parts which may cause spatial errors or even failures in the measurement. The use of lock-in technique and an appropriate source of homogeneous large area laser beam illumination is essential to receive good results on low quality materials.

It is well known from simulations that the dark and illuminated current paths in solar cells may differ considerably. Spatially resolved images of power losses in solar cells can be measured under illumination in different modes to show different loss mechanisms: